# The Calzarossa & Serrazi 1985 Model

This is actually a model of the arrival process in an interactive
environment, rather than a model of a parallel workload.
Its distinction lies in modeling the daily cycle of job submittals,
with peaks in the morning and afternoon, and a drop at lunchtime.

### Arrival Process

The arrival process is defined by a function *lambda(t)* which
gives the arrival rate for time *t*.
The proposed function for "normal" days is a degree-8 polynomial:
$lambda(t)\; =\; 3.1\; -\; 8.5\; t\; +\; 24.7\; t2+\; 130.8\; t3+\; 107.7\; t4-\; 804.2\; t5-\; 2038.5\; t6+\; 1856.8\; t7+\; 4618.6\; t8$
Where *t* is in the range [-0.5..0.5], and should be scaled to
the range from 8:30 AM to 6:00 PM.
Additional details are available in the referenced paper.

Note that this model is suitable for a time-driven simulation, where
one wishes to simulate the correct number of arrivals for each minute
of the day.
Some work is needed to transform this for use in an event-driven
simulation, where you actually need the distribution of interarrival
times.

Parallel Workloads Archive - Models